This invention relates to packaging for smoking articles such as cigarettes, cigars and cigarillos. For convenience and brevity these will be referred to herein as cigarettes.
The object of the present invention is to provide packaging for cigarettes which acts as an effective barrier against ingress and egress of humidity or ingress of contaminants during transport and storage of the packaged cigarettes, but which also allows maintenance of that effective barrier property even after the package has been first opened by the user. In other words, we are providing a resealable barrier layer in cigarette packaging.
The provision of barrier layers either as an inner wrap of a cigarette carton or an outer wrap or both is commonplace. Provision is more or less essential if cigarettes are to have any sort of commercial shelf life in zones having hostile climatic conditions, especially in high temperature, high humidity zones.
But as far as we are aware all such barrier layers so far provided, whether internal or external, have been destroyed in their barrier function when the user first opens the package. Typically, an outer barrier layer has a tearstrip which the user operates to separate halves of the outer wrap which is then discarded, or a barrier layer within a cigarette carton (or surrounding a soft wrap package) although not usually discarded once the package is opened has a permanent opening formed in it by the user when he first gains access.
U.S. Pat. No. 4,763,779 shows a tin-foil inner wrapping for a Laube-type box where a flap of that wrapping may be brought down over an access aperture, and overlap the edges of the aperture. It may have a "peel-seal" connection to the edges it overlaps.